We likewiſe obſerved large maſſes of ſilex in very cloſe ſtrata, which bore a great reſemblance to petrified wood.
One of our carpenters killed an amphibious animal of the ſpecies known by the name of phoca monachus, about ſix feet in length.
Phyſiologiſts have explained in a very ingenious manner how amphibious animals are enabled to remain ſo long under the water by means of the foramen ovale; but, upon examining the heart of this animal with the utmoſt attention, I did not find that it had any foramen ovale. Probably the ſame may be the caſe with many other amphibious animals. By purſuing theſe reſearches we may one day diſcover the true cauſe of the aſtoniſhing faculty poſſeſſed by theſe animals, of living equally well both in the air and in the water.
Each ſide of its lungs is divided by a tranſverſe fiſſure into two lobes.
The ſtomach, which reſembles in ſhape very nearly that of a hog, contained a large quantity of calcareous ſand, amongſt which I obſerved ſeveral ſhell-fiſh that were ſtill entire. The firſt part of the function of digeſtion in this animal ſeems to conſiſt in deſtroying the ſhell in which the fiſh is encloſed, whereby a quantity of ſand is produced in its ſtomach, which does not appear
